High-spin states in the mirror nuclei 49Cr and 49Mn

Abstract The γ spectra of the neutron-deficient nuclei 49 Mn and 49 Cr have been observed using the reactions 12 C( 40 Ca, p2n) 49 Mn and 12 C( 40 Ca,2pn) 49 Cr at E (Ca)=160 MeV.Radiation from 49 Mn and 49 Cr was identified by detecting recoil ions in a 0° mass separator. Data from γ-γ, recoil-γ and recoil-γ-γ coincidence spectra and recoil-γ angular correlations allowed the level scheme of 49 25 Mn 24 to be deduced up to 6 MeV (19/2 − ).The levels of the mirror nucleus 49 24 Cr 25 were observed to over 10 MeV (27/2 − ). Relative Coulomb energies for the mirror states were found to have a smooth J dependence. The rotation-like level spacing at low spin is interrupted at J =19/2 − , and this is interpreted as an alignment effect.